Bomber breached 'most secure hotel' in Indonesia

SYDNEY - An Australian living near Jakarta's Ritz-Carlton hotel says he can't understand how a suicide bomber gained entry into what he called the most secure hotel in Indonesia.

Bombs tore through the Ritz-Carlton hotel and the nearby JW Marriott killing at least nine people and leaving over 40 others injured, including two Australians.

Two blasts shook the upscale Mega Kuningan business district in the centre of the city around 8am local time (1pm NZT) on Friday, sending a huge plume of smoke into the sky.

Australian Greg Woolstencroft said he heard the first bomb go off at the Marriott, and was racing outside to see what happened when the second bomb exploded at the Ritz.

He said a suicide bomber had detonated a device in the restaurant of the hotel, the Airlangga, blowing out two sides of the building.

"I was able to get inside the Airlangga restaurant where the second bomb went off (and) I noticed what appeared to be a suicide bomber - by the looks of the body it was badly mutilated," Mr Woolstencroft told media.

"The inside of the Airlangga restaurant has been totally devastated. The bomb has actually blown out on two sides of the building."

Mr Woolstencroft said he had lived in the Ritz-Carlton and couldn't understand how the suicide bomber had breached the hotel's security.

"I've actually lived at the Ritz-Carlton hotel for 12 months ... that hotel has probably got the highest security of any hotel in Indonesia," he said.

"I just don't know how someone could get in there with a bomb, given the level of security, the level of screening people have to go through.

"I don't how that person got that bomb in."

- AAP